Spectrum Piano
Publication information:
Abstract
The visible part of the electromagnetic spectrum is represented by less than an octave of the keys; UV, IR, and microwaves are also indicated.
What it shows:
The keys of a piano are used to represent the electromagnetic spectrum, illustrating the narrow range of frequencies that constitute the portion visible to human sight.
How it works:
An old piano 1 with its center octave of keys (C4=261.6Hz to C5=523.3Hz) colored for the visible spectrum (the seven colors spread to include eight keys). The visible spectrum covers just under 1 octave: violet at 7.5×1014Hz to red at 4.0×1014Hz, whereas human hearing ranges about eleven octaves (20Hz to 20kHz).
The electromagnetic spectrum however covers at least fifty octaves from the radio to gamma radiation; but with the visible region covering this amount of keyboard, the piano can only play near infra-red to near ultra-violet.
Setting it up:
With the keyboard facing the audience. If the lecturer is no maestro on the ivories a volunteer from the audience will be required.
Comments:
A clue to the hidden universe becoming visible to us with UV and IR observing technology can be gotten by playing a little tune on the spectrum piano. Choose a popular piece (something instantly recognizable 2 ), but play it first using only the visible spectrum keys (name that tune?). Extend your technology into the IR, then into the UV.
1 Bogart (New York) Grand Upright
2 Beethoven's Für Elise worked tremendously well, performed by student assistant Alyn Kelley '90.
Full text
The visible part of the electromagnetic spectrum is represented by less than an octave of the keys; UV, IR, and microwaves are also indicated.
What it shows:
The keys of a piano are used to represent the electromagnetic spectrum, illustrating the narrow range of frequencies that constitute the portion visible to human sight.
How it works:
An old piano 1 with its center octave of keys (C4=261.6Hz to C5=523.3Hz) colored for the visible spectrum (the seven colors spread to include eight keys). The visible spectrum covers just under 1 octave: violet at 7.5×1014Hz to red at 4.0×1014Hz, whereas human hearing ranges about eleven octaves (20Hz to 20kHz).
The electromagnetic spectrum however covers at least fifty octaves from the radio to gamma radiation; but with the visible region covering this amount of keyboard, the piano can only play near infra-red to near ultra-violet.
Setting it up:
With the keyboard facing the audience. If the lecturer is no maestro on the ivories a volunteer from the audience will be required.
Comments:
A clue to the hidden universe becoming visible to us with UV and IR observing technology can be gotten by playing a little tune on the spectrum piano. Choose a popular piece (something instantly recognizable 2 ), but play it first using only the visible spectrum keys (name that tune?). Extend your technology into the IR, then into the UV.
1 Bogart (New York) Grand Upright
2 Beethoven's Für Elise worked tremendously well, performed by student assistant Alyn Kelley '90.